Constipation SOS

Please share some good lunch and dinner ideas for peaky eater .she is currently on movicol 2sachet a day and currently under investigation for celiac as she is having hard constipation and her weight loss 75th centile to 25th centile and pead asked for blood test so after they will decided if it’s comes negative or positive but before that what can I offer my baby she likes dry food but very rare she is 100% peaky she likes eggs with cheese so I do loads of other ways to give her some different food but she is bored by this she likes pancake for morning currently not giving her weetavix as it’s giving very hard poop and oats . What can I offer for lunch please share .i had to distract her to get in some food 😭😭😭😭😭she is 15 month old